Machine for thermochemically severing metal workpieces



Nov. 6, 1951 w. J. GREENE 2,574,101

MACHINE FOR THERMOCHEMICALLY SEVERING METAL WORKPIECES 6 Sheets-Sheet 1 Filed 001;. 50. 1948 IO Y I I i+- I N l; K g

g is w p O3 H I r LO r0 INVENTOR kg 8 WILLIAM J GREENE ATTORNEYS Nov. 6, 1951 w.' J. GREENE MACHINE FOR THERMOCHEMICALLY 'SEVERING METAL WORKPIECES 6 Sheets-Sheet 2 Filed Oct. 50, 1948 INVENTOR WILLIAM J GREENE .1. 6 ATTORNEYS Nov' 1951 MACHINEm d gE REE aEA/IICALLY 2,574,101

MN MW 'im'v In L .NW W ii N L) 1 g Q I 00 P H I OOEJ vhiil' LAQEW! W. .4 E i a I i I LL M191 JL-Li 5 jib??? f/ E %g NNNNNN OR WILLIAM J. GREENE BY am. Z1: Q;

ATTORNEYS Nov. 6, 1951 w J. GREENE. 2,574,101

MACHINE 1 0R THERMOCHEMICALLY SEVERING METAL WORKPIECES Filed Oct. 30, 1948 6 Sheets-Sheet 4 FIG.- 5

INVENTOR WILLIAM J.GREENE.

BY y- QWA, Z42) Z ATTORN E'YS Nov. 6, 1951 w. J. GREENE MACHINE FOR THERMOCHEMICALLY SEVERING METAL WORKPIECES 6 Sheets-Sheet 5 Filed Oct. 50, 1948 FIGS FIG?

INVENTOR WILLIAM J. GREENE Nov. 6, 195] MACHINE FOR GREENE 2,5 74, 1 0 l THERMOCHEMICALLY SEVERING METAL WORKPIECES 6 Sheets-Sheet 6 Filed Oct. 30. 1948 hm mm INVENTOR WILLIAM J. GREENE ATTO R N EYS Patented Nov. 6, 1951 MACHINE FOR THERMOCHEMICALLY SEVERIN G METAL WORKPIECES William J. Greene, Plainfield, N. J assignor to Air Reduction Company, Incorporated, a corporation of New York Application October 30, 1948, Serial No. 57,514

Claims.

This invention relates to torch cutting machines of the type used to thermochemically sever bars, beams, rails, billets, and the like, by the well known oxy-iuel gas cutting method.

Many torch cutting machines have been designed for this purpose but each of them has had some inherent difficulty that limited its field of use, impaired its efiiciency, or reduced its useful life. For example, most of them have been able to cut rounds, or workpieces of rectangular section, or some special structural shape, but not all of them, nor have they been able to cut all sizes of the one or more shapes for which they were designed. Furthermore, the machines heretofore proposed have been so constructed that they could sever a workpiece only when it was accurately positioned with respect to the machine, or in cases where some latitude in work position was tolerable a guide or gauge of some kind was required which had to rest on the workpiece or contact with it. Also, in

most of the machines heretofore proposed, the working parts have been subjected to heat and I corrosive fumes from the cutting operation which Fig. 3 is a vertical transverse section taken along line 3-3 of Fi 2;

Fig. 4 is a plan view of the machine with the auxiliary torches and their associated parts shown in phantom;

Fig. 5 is a horizontal section taken along line 55 of Fig. 2;

Fig. 6 is an enlarged vertical section of the distal end of the boom and the parts associated with it;

Fig. 7 is an enlarged side elevation of the counterbalance employed in the machine, some parts being shown in vertical section;

Fig. 8 is a plan view of one of the auxiliary casing and conduit structures through which gases and cooling medium are delivered to the auxiliary torches; and

after referred to as the main post.

Fig. 9 is a side elevation of the auxiliary casing and conduit of Fig. 8.

The outward appearance of the machine is illustrated in Fig. 1. The main frame of the mae chine is a weldment of structural members. Two channel members (see also Figs. 2 and 3) are welded to end plates 2| and 22 which are in turn welded to a base plate 23. Brackets or braces 24, welded to the base plate and the channel members 23, add rigidity to the structure. Above the channels 23, and welded to them, are a pair of inclined side plates 25 which are welded at their ends to the end plates 2| and 22. These side plates contain access doors 26. Above the side plates and also welded to the end plates are smaller channel members 21. Brackets 28 (Fig. 3) are mounted on the channels 21 and support the main pivot pin bearings 29. A dust cover 3| completes the main frame assembly.

' A horizontal pin 3| is journalled in the bearings 29 the axis of which constitutes the fixed pivot axis for a pantograph structure that operates in a substantially vertical plane. The four pivotally connected portions that constitute the pantograph structure are a pair of upper and lower parallel arms and 36 (Fig. 2), hereinafter referred to as the boom and the control arm respectively, and two upright parallel arms 31 and 38. The forward upright arm 31 is herein- The rear upright arm 38, in the particular machine illustrated in the drawings, is not a single member but a pair of links located at opposite sides of the pantograph. The upper end of the main post 31 is pivotally connected to the boom 35 by a pivot pin 39. Its lower end is pivotally connected to the control arm 36 by a pivot pin 391. The lower end of each of the links 38 is pivotally connected to the control arm 36 by a pivot pin 392., and the upper end of each of these links is pivotally connected to the boom 35 by a pivot pin 393.

structurally the main post 31 consists of a pair of vertical channel members 4|! (Fig. 3) positioned with their channels facing each other and tied together by a bushing 4| surrounding the main pivot pin 3|, a bushing 42 surrounding the pivot pin 391, and by a tubular connecting member 43. Near the top of the main post 31 the flanges of the channel members are cut away to form a yoke in which bearings 44 are The control arm 36 is also formed of two channel members 46 positioned with their channels facing outwardly and held in spaced relation by spacers 41 (Fig. As best seen in Figs. 3 and 5, bearings 48 are mounted in the channel members 46, and the ends of the pivot pin 391 which pivotally connects the main post 3! and the control 'arm, are journalled in these bearings.

The details of the boom are as follows: Two channel members 50 (Fig. 3) are positioned with their channels facing each other and are connected by upper and lower plates 51 welded to them. A light-gauge dust cover 52 fits on top of this structure and houses a number o'fthe parts of the boom. A bracket 53 (Fig. '6) is pivotally connected to the distal end oi the boom by a pivot pin 54. A conventional square torch bar 55 is securely attached to the bracket 53. A bracket 56 which is adjustable along the torch bar, and which may be clamped in its adjusted position to the torch bar, supports a conventional oxy-fuel gas cutting torch 5-1. i I

As will be clear from 'Fig. 2, the pivot pin 3| pivotally supports the main post 3! intermediate its pivotal connections "to the boom and control arm. Therefore, any'm'ovement of 'a predetermined point'on the control arm willr'esult in an opposite, proportional, and parallel'movement of a point on the boom if such point is-in a straight line with the predetermined point on thecontrol arm and the axis of the pivot pin 3|. The pivot .pin 54, by means of which the torch is mounted on the boom, is located at such'a point on the boom if it is desired that the torch'exactly reproduce the movement "imparted to the predetermined point on the control'arm,'and'power driven 'mechanisms are provided to impart vertical and horizontal components of movement to'the predetermined point on the control arm to thereby 'move'the torch in the desired path.

At the predetermined point on the control arm 36 there is provided a horizontal pin 58 (Figs. 2 and '5) which extends transversely through 'the control arm. The verticalandhorizontal components 'of movement are imparted to this pin. This 'is preferably done by combining rectilinear components df moveinent'providedby two power operated straight-line mechanisms working at right'angles to each otherjand both actingfon the pin 58. d bestillustrated'in Fig.2 and are denoted in general by the reference character's'sr and S2. They are'pre'ferably well-known Roberts straight-line mechanisms. The straight-line mechanism S1 that guides the pin 58 in an approximate straight line when the pin is moved horizontally comprises a triangular shaped 'plat'e'59 pivoted "at its apex end to the pin58 and extending upwardly from it. A pair of links are pivotally'c'o'nnected at their upper ends to the two upper corners of the plate 59 and extend downwardly at a divergent angle and are pivoted at "their lower ends to the two lower corners of a "plate 6| which is parallel to the plate 59. This plate Si is secured along its upper edge to a horizontally disposed plate 62. It will thus be evidentthat when the plate 62 is held against vertical movement while the pin 58 is moved horizontally, the pin will be guided in an approximately straight horizontal line. The action is illustrated in Fig. 20, from which it will be seen that if a horizontal component of movement is imparted to the pin 58 to cause it to move toward the left from the position shown in Fig. 2, the links 60 will cause movement of the triangular plate "59 in The straight-line mechanisms are such a Way that the pin 58 during its movement will follow an approximately straight horizontal line. The second straight-line mechanism S2, that guides the pin 58 in an approximately straight line when the pin is moved vertically comprises a triangular plate 59f pivoted at its apex end to the pin 58 alongside of the triangular plate 59. This plate extends horizontally to the right of pin 58 as viewed in Fig. 2. A pair of links 60' pivotally connect the right-hand corners of plate 59' to the left-hand corners of a plate Bl which in turn is secured along its right-hand edge to a plate 62'. Thus it will be seen that the second straight-line mechanism S2 is similar to the one previously described but its axis is horizontally disposed instead of vertically disposed.

.Wh'en the plate 62 is held against horizontal movement while the pin 58 is moved vertically, it will 'be evident that the straight-line mechanism S2 will cause the pin 58 to move along an approximately straight vertical line, the action or the triangular plate 59 and the links 50 being similar to the action of the cor-responding plate and links illustrated in Fig. 2a.

The vertical component of movement of the pin 58 is provided by an electric motor '63 which rotates a-shaft t4 through a speed reduction unit 65. A pinion'EG on the shaft 64 meshes with a rack 61 which is fixed to a vertical ram 88. The above-described plate 62, to which the straightline mechanism S1 is attached, is secured to the lower' end of this ram. Thehorizontal component of movement ofthe-pin 58 is provided by a second electric motor 69 and a horizontal ram 10. The above-described plate 52", to which the second straight-linemechanism S2 is attached, is secured to the left-hand end of this ram as viewed in Fig. 2. It will thus be evident that'the torch carried by the boom may be made to follow any desired path by properly'operatmg the two electric motors 63 and 69. This may be done by manual control of the motors or by automatic control of them in any suitable way.

To maintain the balance of the machine in all positions and thereby reduce the operating power required, an adjustable counterbalance H '(Fig. 2) "is employed which is operatively coirnected to the lower end or the main post 3'1. This counterbalance is shown by itself in Fig. 7 on an enlarged scale and partly in section. Both "ends are identical. It comprises a tube 12 through which 'a rod 13 passes. A 'coil spring {[4 surrounds the rod within the tube. Bushings 15 are'slipped over the rod at opposite ends of the spring andcaps "I6 arescreweu onth'e tube ends. Stop nuts 11 are screwed on the ends 0f the rod and engage the bushings '55. One end 18 of the rod is pivotally connected to the lower end of the main post '31 as shown in Fig. 2. The tube 12 is pivotally modri-t'ed on the base of the machine as shown at it. Thus it will be seen that spring i4 is compressed as the lower end of the main post 3 7 deviates in-eithcr direction from its mid position shown in Fig. 2,

. thereby tending to offset the unbalance or the machine brought about by deviation of the panto- "graph structure from its mid position. The stop nuts l'l are adjustable to compensateicr the weight of additional torches and their assorted parts when they "are provided.

The purpose of the pivotal connection between the bracket 53 (Fig. 6) and the boom isto permit the torch to be adjusted angularly. The necessity of this is twofold. First, as the pantograph structure operates to move the torch vertically the boom necessarily pivots about the pivot pin 39. To maintain the torch vertical (or at any preselected angle) it is therefore necessary to rotate the bracket 53 about the pin 54. Second, it is desirable to be able to use the torch either vertically or inclined to the vertical with remote control of the angle of inclination. To accomplish this a rod 88 (Fig. 6) is pivotally connected to the bracket 53 eccentrically with respect to the pivot pin 54. The opposite end of the rod 88 is pivotally connected to one arm of another bracket or crank 8| (Fig. 2) mounted to turn about the axis of pivot pin 39. The other arm of-this bracket is pivotally connected to the upper end of a rod 82, the lower end of which ispivotally connected to one arm of another bracket or crank 83 mounted to rotate. about the axis of the main pivot pin 3|. The'other arm of this bracket is pivotally connected by an arm 84 to a motorized linear actuator 85, i. e.,

a motorized jack-screw. Thus any given angular position of the torch, such as the vertical position illustrated in Fig. 2, will be maintained regardless of the position assumed by the pantograph structure provided the motorized jackscrew 85 is not actuated. This is because horizontal components of movement of the boom will not tend to change the inclination of the torch anyhow since during such movements of the boom the rods 80 and 82 have no efiect in changing the angularity of the torch, but when the pantograph structure operates to move the torch vertically and the boom pivots about pivot pin 39, then the rod 80 and the boom along with the vertical arm of bracket 8| and the vertical arm of bracket 53' will act-like a folding parallelogram structure that changes the angular relation between the torch and the boom as the boom pivots about pin 39 but preserves the original angular position of the torch with respect to the work.

It must be borne in mind, of course, that during this functioning of the folding parallelogram structure of which the rod 80 forms one member, the bracket 8| is held relatively stationary by the rod 82, bracket 83, and motorized jackscrew 85. To vary the angular position that will be maintained by the torch through all positions of the pantograph structure it is only necessary to actuate mechanism 85, which may be done remotely. The mechanism 85 may of course be actuated during movement of the pantograph structure to adjust or continually change the angular position of the torch while the cutting operation is progressing, should this be necessary or desirable.

The gases and cooling medium are supplied to .the torch through the cover 52 on the boom and through a duct 86, as best shown in Figs. 2 and 4. Fittings are provided at the rear end of the boom to receive acetylene or other fuel gas, preheat oxygen, and cutting oxygen. Each line is controlled by a solenoid valve, the three valves being denoted 81, 88 and 89 (Fig. 4). From the valves the gases pass through hoses, denoted .collectively at 98, which extend through the cover 52 and then through duct 86 to the torch. There are two blowers 9| and 92 mounted on the boom within the cover 52 that provide the necessary air cooling. Blower 9| forces cooling air along the boom and through duct 88. Blower .92 forces cooling air through a pipe 93 (Fig. 2) which leads to the interior of the square torch 'bar 55, thereby cooling it.

. The machine as thus far described has only one cutting torch mounted on the torch bar 55.

6 Additional torches may be mounted on the torch bar if desired as shown at 51a and 511) (Fig. 1). For each additional torch there is mounted on the boom an auxiliary casing containing the solenoid gas valves for that torch, and a duct leading from the auxiliary casing to the torch through which pass the gas hoses and the cooling medium for the torch. One of these auxiliary casings is illustrated in Figs. 8 and 9. The auxiliary casing itself is shown at 94. It contains three solenoid valves 95 for the three gases delivered to the corresponding additional torch. A duct 96 extends from the casing 94 to the torch, and gas hoses 91 lead from the solenoid valves to the torch through this duct. A blower 98 is located in the auxiliary casing 94 to force cooling air into and through the duct 98 to the torch. If a water-cooled torch is employed, inlet and outlet fittings such as those shown at 99 are provided. Flexible tubes I08 connected to these fittings pass through the duct 98 along with the gas hoses and conduct the cooling water to and from the torch at the end of the duct. Brackets l0! and H12 ,(Fig. 9) secured respectively to the bottom of the duct 96 and the bottom of the auxiliary casing 94 clamp on round rods I83 and HM (Figs. 1 and 4) projecting from the side of the machine and thereby support the casing and its duct in proper position. Although Fig. 1 shows only two additional torches 51a and 512), Fig. 4 illustrates by broken lines the manner in which six additional torches may be employed and each provided with an auxiliary casing and duct of the kind illustrated in Figs. 8 and 9.

7 Thus it will be seen that a cutting machine has been provided by which all sizes and shapes of work may be severed in whatever location it comes through on the roll table; that is, the work does not require accurate positioning with respect to the machine. The operating mechanism is remote from the place where the cutting operation occurs and is therefore not likely to be damaged by the heat, fumes, and flying slag from the cutting operation. The control is very flexible and may be manual, semi-automatic, or

automatic, but the particular nature of the control means forms no part of the invention. The machine may be remotely controlled at all times since it is not even necessary to operate any controls on the machine proper to adjust the torch angle.

The movement at point 54 where the torch or torches are mounted on the boom may of course be of difierent magnitude than the movement at point 58, depending upon the position of the pivot pin 3| along the length of the main post 31. Preferably. the movement at point 58 is an amplification of the movement at point 53. In the particular machine illustrated in the drawings the pivot pin SI for the main post 81 is so located that the amplification ratio is 2:1, i. e., a given amount of movement imparted to the pin 58 will produce twice that amount of movement at the pin 54 and at the torch tip or tips.

While the two straight-line mechanisms above described are preferably of the Robert type, there are other well-known types of straight-line mechanism that may be used if desired. These include Watts straight-line mechanism and Tchebicheffs straight-line mechanism.

I claim:

. 1. A machine for thermochemically severing metal workpieces comprising a frame, a pair of upper and lower arms pivotally connected to a pairpf upright arms to form a pantograph strucmounted on the upper arm, a horizontal pin carried by the lower arm, and means for applying vertical and horizontal components of movement to said pin including a vertically movable member, a straight-line mechanism carried by such member and operatively connected to said pin, a horizontally movable member, a second straight-line mechanism carried by said horizontally movable member and operatively connected to said pin, the first-named straight-line mechanism being adapted when the vertically movable member on which it is carried is held stationary and the horizontally movable member is moved horizontally to guide said pin in an approximately straight horizontal line, and the second straight-line mechanism being adapted when the horizontally movable member on which it is carried is held stationary and the vertically movable member is moved vertically to guide said pin in an approximately straight vertical line.

10. A machine for thermochemically severing metal workpieces comprising a frame, a pair of upper and lower arms pivotally connected to a pair of upright arms to form a pantograph structure operating in a substantially vertical plane, one arm of said first-named pair being a torchcarrying arm and the other one being a control arm, a pivotal connection between one of the upright arms and the frame affording a fixed horizontal axis about which such arm may pivot, a horizontal pivot pin carried by the torch-carrying arm, a torch holder mounted on said pin so that it can swing about the axis thereof, a gas cutting torch mounted in said holder, means for applying vertical and horizontal components of movement to a predetermined region of the control arm whereby the torch may be made to move in any direction in a vertical plane, and means for adjusting the angular relation between the torch and the torch-carrying arm comprising actuating means mounted on the frame and connections extending therefrom to the torch holder, said means being operable independently of the movement of the pantograph structure.

11. A machine for thermochemically severing metal workpieces comprising a frame, a pair of upper and lower arms pivotally connected to a pair of upright arms to form a pantograph structure operating in a substantially vertical plane, one arm of said first-named pair being a torchcarrying arm and the other one being a control arm, a pivotal connection between one of the upright arms and the frame affording a fixed horizontal axis about which such arm may pivot, a horizontal pivot pin carried by the torchcarrying arm, a torch holder mounted on said pin so that it can swing about the axis thereof, a gas cutting torch mounted in said holder, means for applying vertical and horizontal components of movement to a predetermined region of the control arm whereby the torch may be made to move in any direction in a vertical plane, a movable member, a connection from said torch holder to said member for adjusting the angular relation between the torch and the torch-carrying arm when said member is moved and for maintaining the axis of the torch in a predetermined angular position relative to a horizontal plane during movement of the pantograph structure when said member is held stationary, and means operable independently of the movement of the pantograph structure for moving said member or for holding it stationary during movement of the pantograph structure.

arm and the frame affording a fixed horizontal one arm of said first-named pair being a torchcarrying arm and the other one being a control arm and one of the upright arms being a main supporting arm for the pantograph structure, a pivotal connection between said main supporting axis about which such arm may pivot, a horizontal pivot pin carried by the torch-carrying arm, a torch holder mounted on said pin so that it can swing about the axis thereof, a gas cutting torch mounted in said holder, means for applying vertical and horizontal components of movement to a predetermined region of the control arm whereby the torch may be made to move in any direction in a vertical plane, a rotatable member mounted to rotate about the axis of the pivotal connection between the torch-carrying arm and one of the upright arms, and a rod pivotally connected at one end to said member in eccentric relation to said last-named pivotal connection and pivotally connected at its other end to the torch holder in eccentric relation to the axis of the pin on which the torch holder is mounted whereby the axis of the torch may be maintained in a predetermined angular position relative to a horizontal plane during vertical movement of the torch end of the torchcarrying arm when said rotatable member is held relatively fixed during operation of the pantograph structure and whereby the angular relation between the axis of the torch and the torchcarrying arm may be varied at any time by rotation of said rotatable member about its axis of rotation.

13. A machine in accordance with claim 12 having actuating means on the frame operatively connected to said rotatable member whereby the rotatable member may be held in relatively fixed position during operation of the pantograph structure or may be rotated at any time.

14. A machine for thermochemically severing metal workpieces comprising a frame, a pair of upper and lower arms pivotally connected to a pair of upright arms to form a pantograph structure operating in a substantially vertical plane, one arm of said first-named pair being a torchcarrying arm and the other one being a control arm and one of the upright arms being a main supporting arm for the pantograph structure,

a pivotal connection between said main supporting arm and the frame affording a fixed horizontal axis about which such arm may pivot, a gas cutting torch mounted on the torch-carrying arm, an electric motor operatively connected to a predetermined region of the control arm so as to apply a vertical component of movement to such region, and a second electric motor operatively connected to such region of the control arm so as to apply a horizontal component of movement thereto.

15. A machine for thermochemically severing metal workpieces comprising a frame, a pair of upper and lower arms pivotally connected to a pair of upright arms to form a pantograph structure operating in a substantially vertical plane, one arm of said first-named pair being a torchcarrying arm and the other one being a control arm and one of the upright arms being a main supporting arm for the pantograph structure, a pivotal connection between said main sup- 11 12 porting armand the frame affording a fixed r REFERENCES CITED 'horizontal.axis about which such arm may pivot The following references are of record in the a gas cutting torch mounted on the torch-carryme of this patent:

in-g arm, means operatively connected to a predetermined region of one of the arms constitut- UNITED STATES PATENTS ing said pair of upper and lower arms for apply- 5 Number Name Date ing a vertical component of movement to such 669,549 Roche Mar. 12, 1901 region, and means operatively connected to said 1,826,164 Carrier, Jr., et a1. Oct. 6, 1931 region of such arm and operable independently 2,289,968 Jones July 14, 1942 of said first-named means for applying a hori- 2,404,600 Scovill, Jr. July 23, 1946 zontal component of movement to such region. 2,413,088 Urquhart Dec. 24, 1946 WILLIAM J. GREENE. 

